Definition: In this task, you are given an input list A. You need to convert all the alphabets in the list with a number representing their position in the English alphabet. E.g., replace A by 1, B by 2, a by 1, b by 2, and so on.
Input: ['b', 'O', 'K', '3049', 'M', '5171', 'i']

2, 15, 11, 3049, 13, 5171, 9